Tyre Pressures

[Dabz]

Just checked my tyre pressures on the bike, car and van - scarey stuff! All 3 were down, the bike's rear was 0.4bar below what it should be and the front 0.2bar below. The van...well almost 1 bar below on each of the rear tyres, and all 4 car ones were well below too.

I really should check more often...I'm very bad at doing basic maintenance and check maybe twice a year

[GixerBoy]

What are the recommended pressures for the trumpet dabz......in psi please!

[R1chie]

warm or cold tyres?

[Gav]

Cold tyres the pressure for the triumph should be
Front 36psi
Rear 42psi

[GixerBoy]

Pretty much the same as all the rest then!
Drop the rear to 36 Dabz but leave the front standard. (36psi front and rear solo,or 38 rear two up)

[b_1_rd]

Interesting. Whys that mate? Mine is 42 rear too, better at 36?

[GixerBoy]

Mate,originally got the info from Mark at MH Racing the first time I went there a few years ago......He was saying that 42 rear is just putting money in the tyre manufactures pockets......
So I started running my rear at 38.....Then about a year or so ago,my bike was in Crescent for something or other and I asked them what they thought and they said 36 front and rear.......So down came the rear to 36........Wouldn't run it any other way now mate......Even 38 in the rear makes a huge difference to mine,thats why I run 38 two up,can really feel the change!
Give it ago,see what you think.......You will defo get more milage out of the rear for starters!

GB.

[b_1_rd]

I'll give it a go. Cheers.

[Gav]

Lowering the tyre pressures does 2 things...

1st It allows the tyre to flex more, thus generating more heat and a larger contact patch on the road. The reason you will get more milage from a rear running a lower pressure is a direct result of the above, with the grip gained from the extra heat and the larger contact patch the tyre will spin up a lot less and put the power down on the road better, less spin means less wear on the tyre...simple

2nd This is the iffy one, due to increased running temperature it can cause the tyre to overheat which can in some cases cause failiure of the tyre if it is used mainly for straight line work...ie motorways

With that in mind GB is correct, modern tyres on SPORTS bikes will perform better running somewhere around 32/34 front and 36/38 rear depending on load and type of riding you do.
Tyre manufactures reccomend 36 front 42 rear on most modern bikes because the testing they do indicates that for 90% of appliacations it is the best pressures to run. Its not just worked out on pressure, but the volume of air in the tyre and wheel. They recommend the pressure that their tests show will give best life/grip/RELIABILTY/fell for the majority of bikers and bikes.

The only way to know if a lower pressure works for you is to try it and see what you think, if you dont like it adjust it a couple of psi at a time till you are happy with it.

Oh just another quick pointer, those of you with larger type bike(tourers) may find that adjusting the pressures away from recomended pressures will affect stability in a straight line due to the load on the tyre so beware.

Gav

[Rod]

My Hog certainly runs better with slightly lower tyre pressures